Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2011
Sammendrag
Recent research on how the structure and physiological development of red raspberry (Rubus idaeus L.) plants are controlled by genotype and the climatic environment is reviewed. Some older work, specially on plant structure relations, is also included. Physiological differences between annual- and biennial-fruiting plant types are highlighted. One major difference is the different requirements for flower formation. While biennial-fruiting cultivars have an absolute low temperature (≤ approx. 15°C) requirement for floral initiation, annual-fruiting cultivars readily initiate floral primordia at temperatures as high as constant 30°C. Also, while biennial-fruiting cultivars are facultative short-day plants with a critical photoperiod of 15 h at intermediate temperatures, flowering is promoted by long photoperiods in at least some annual-fruiting cultivars. However, the essential difference that determines whether the shoot life-cycle becomes annual or biennial is that, in biennial-fruiting genotypes, floral initiation is linked to the induction of bud dormancy, whereas in annual-fruiting cultivars, floral initiation is followed by direct flower development. Although this is genetically determined, it is a plastic trait that is subject to modification by the environment. Thus, at low temperatures and short photoperiods, the majority of initiated buds do enter dormancy also in annual-fruiting cultivars, with tip-flowering as a result. Practical applications are discussed, and it is concluded that our present physiological knowledge-base provides excellent opportunities for manipulation of raspberry crops for out-of-season production and high yields. It also provides a firm platform for further exploration of the underlying molecular genetics of plant structures and response mechanisms.
Sammendrag
The collapse of the Soviet Union in the Central Asian countries has led to enormous challenges for them in ensuring a sustainable environment. Weak economies and lack of expertise in environmental sciences were important reasons for the Norwegian support to the environmental sector in this region. The State Forest Service of the Kyrgyz Republic and the Norwegian Forestry Group initiated the TEMP project, later renamed TEMP-CA, in the Kyrgyz Republic in 2004. Activities in the Republic of Tajikistan were included in 2007 and in the Republic of Uzbekistan from 2008. The forestry sectors in the Kyrgyz Republic and neighbouring countries in Central Asia, surrounding the Fergana Valley, are closely linked to the environmental and emergency planning sectors. Overgrazing and overharvesting have contributed to a dramatic decline in forest cover. The TEMP-CA project contributes to a better understanding of environmental problems and sustainable forestry in Central Asia. The TEMP-CA project has promoted institutional co-operation between Norway and the Central Asian countries as well as between different institutions both within and between the countries of Central Asia. Increased expertise for scientists, fieldworkers, laboratory staff and staff in different forest departments as well as institutional development in general are important outputs from the TEMP-CA project. The Gauyan monitoring site in Batken oblast in the Kyrgyz Republic was the seventh of ten monitoring sites established in forests in Central Asia: 1: ”Kara-Koi” in the Osch oblast, the Kyrgyz Republic. 2: ”Sogot in the Jalal-Abad oblast, the Kyrgyz Republic. 3: “Dugoba” in Batken oblast, the Kyrgyz Republic. 4: “Besh-Tash” Talas oblast, the Kyrgyz Republic. 5: “Sary-Chelek”, in Jalal-Abad oblast, the Kyrgyz Republic. 6: “Navobod” in Sogdi oblast, the Republic of Tajikistan. 7: “Gauyan” in Batken oblast, the Kyrgyz Republic. 8: “Zaamin” in Djizak region, the Republic of Uzbekistan. 9: “Urumbash” in Jalal-Abad oblast, the Kyrgyz Republic. 10: “Umalak Teppa”, Tashkent region, the Republic of Uzbekistan.
Forfattere
Mats HøglindSammendrag
To develop mechanistic models for winter survival of grasses under climate change, more knowledge is needed of photosynthetic activity at low irradiance and temperature. Photosynthetic activity of small stands of Lolium perenne was continuously studied for up to two weeks under low photosynthetic photon flux density (PPFD) in the air temperature range from -3°C to +9°C. The photosynthetic rate of plants growing at 2, 6 and 9°C was similar at 120 µmol m-2 s-1 PPFD but the rate increased with increasing PPFD at all temperatures, particularly 9°C. Light saturation of photosynthesis was reached at approx. 300 µmol m-2 s-1 at 2 and 6°C, and at approx. 600 µmol m-2 s-1 at 9°C. At 300 µmol m-2 s-1, the CO2 exchange rate (CER) at 2°C was approx. 60% of that at 9°C. When the temperature increased gradually from 0°C at start to +5°C at the end of the 8-h photoperiod, CER decreased by about 20% compared with that at constant 5°C. Changing the temperature from constant +5°C to a diurnal variation between -2 and +2 °C gradually decreased daytime CER to approx. 10% after five days, partly due to leaf area losses (~50% loss) when the poorly acclimatised plants were exposed to frost. At start of the photoperiod at -2°C CER was negative, but became slightly positive when temperature exceeded -1°C after two hours. Total daily photosynthesis was negative due to night-time respiration in this treatment. Soil heating to avoid freezing when the diurnal air temperature fluctuated between -3 and + 3°C had no effect on CER at this low PPFD level (150 µmol m-2 s-1). In contrast to the -2/+2°C treatment, total daily photosynthesis was slightly positive in the -3/+3°C treatment, where the plants were better acclimatised to frost. Increasing the CO2 concentration from 350 to 600 µmol mol-1 had no effect on CER at 2 and 6°C, but increased it by 20% at 9°C. The data indicate that the minimum temperature for photosynthesis in the cultivar studied is about -4°C. The results can be applied in different photosynthesis models.
Sammendrag
Norwegian lamb meat production is mainly based on free grazing in mountainous pastures during the summer. Prior to slaughter in the autumn, some lambs not big enough for slaughter are finished on e.g. cultivated pastures. This study looked at the feed quality of different forages, and the effect on lamb meat quality. Lambs grazed on mountain pastures at Kvaløya in Northern Norway (69°N) and Sør-Fron in Mid Norway (58°N) in 2007, and a subgroup at each location was finished on cultivated pastures for 6 weeks prior to slaughter in September. The fiber content was significantly higher in the cultivated pasture in Mid Norway compared to the mountain pasture while no differences between pastures in Northern Norway were found. In Mid Norway the content of polyunsaturated fatty acid (18:3) was significantly higher in meat from lambs grazing the mountain pasture compared to lamb grazing the cultivated pasture. For Northern Norway, the opposite pattern was observed. The higher 18:3 content may be attributable to lower fiber content at the mountain pasture. In our study, there appears to be an effect of fiber content on the fatty acid composition in lamb meat.
Forfattere
Vibeke LindSammendrag
Norwegian lamb meat production is mainly based on free grazing in mountainous pastures during the summer. Prior to slaughter in the autumn, some lambs not big enough for slaughter are finished on e.g. cultivated pastures. This study looked at the feed quality of different forages, and the effect on lamb meat quality. Lambs grazed on mountain pastures at Kvaløya in Northern Norway (69°N) and Sør-Fron in Mid Norway (58°N) in 2007, and a subgroup at each location was finished on cultivated pastures for 6 weeks prior to slaughter in September. The fiber content was significantly higher in the cultivated pasture in Mid Norway compared to the mountain pasture while no differences between pastures in Northern Norway were found. In Mid Norway the content of polyunsaturated fatty acid (18:3) was significantly higher in meat from lambs grazing the mountain pasture compared to lamb grazing the cultivated pasture. For Northern Norway, the opposite pattern was observed. The higher 18:3 content may be attributable to lower fiber content at the mountain pasture. In our study, there appears to be an effect of fiber content on the fatty acid composition in lamb meat.
Populærvitenskapelig – Många nyheter bland skånska blommossor
Torbjörn Tyler, Hans Haavardsholm Blom
Forfattere
Torbjörn Tyler Hans Haavardsholm BlomSammendrag
[A lot of novelities in Schistidium in the province of Skne, southern-most Sweden.] Based on revision of c. 200 collections of Schistidium made during the ongoing survey of the bryophyte flora of the province of Skne, it is concluded that although S. apocarpum (s.str.) and S. crassipilum are by far the most frequent species a fair number of other taxa occure in the province.Thus, single collections of four species not previously documented from the province, viz. S. boreale, S. dupretii, S. robustum and S. trichodon, have been revealed. For all of these species this makes an extention of their known range of more than 500 km, indicating that also species not known from adjacent regions have to be considered when identifying material of this genus.A combination of efficient long-range dispersal and an ability to colonize virgin substrates may explain their, possibly short-lived, emergence far outside their established range: Further surveying is needed to document their distribution and frequency in the province, and their ability to persist at the localities.In total, 13 taxa of the genus are now documented from the province.
Forfattere
Erik Næsset Terje Gobakken Svein Solberg Timothy Gregoire Ross Nelson Göran Ståhl Dan Johan WeydahlSammendrag
There is a need for accurate inventory methods that produce relevant and timely information on the forest resources and carbon stocks for forest management planning and for implementation of national strategies under the United Nations Collaborative Program on Reduced Emissions from Deforestation and Forest Degradation in Developing Countries (REDD). Such methods should produce information that is consistent across various geographical scales. Airborne scanning Light Detection and Ranging (LiDAR) is among the most promising remote sensing technologies for estimation of forest resource information such as timber volume and biomass, while acquisition of three dimensional data with Interferometric Synthetic Aperture Radar (InSAR) from space is seen as a relevant option for inventory in the tropics because of its ability to “see through the clouds” and its potential for frequent updates at low costs. Based on a stratified probability sample of 201 field survey plots collected in a 960 km2 boreal forest area in Norway, we demonstrate how total above-ground biomass (AGB) can be estimated at three distinct geographical levels in such a way that the estimates at a smaller level always sum up to the estimate at a larger level. The three levels are (1) a district (the entire study area), (2) a village, local community or estate level, and (3) a stand or patch level. The LiDAR and InSAR data were treated as auxiliary information in the estimation. At the two largest geographical levels model-assisted estimators were employed. A model-based estimation was conducted at the smallest level. Estimates of AGB and corresponding error estimates based on (1) the field sample survey were compared with estimates obtained by using (2) LiDAR and (3) InSAR data as auxiliary information. For the entire study area, the estimates of AGB were 116.0, 101.2, and 111.3 Mg ha−1, respectively. Corresponding standard error estimates were 3.7, 1.6, and 3.2 Mg ha−1. At the smallest geographical level (stand) an independent validation on 35 large field plots was carried out. RMSE values of 17.1–17.3 Mg ha−1 and 42.6–53.2 Mg ha−1 were found for LiDAR and InSAR, respectively. A time lag of six years between acquisition of InSAR data and field inventory has introduced some errors. Significant differences between estimates and reference values were found, illustrating the risk of using pure model-based methods in the estimation when there is a lack of fit in the models. We conclude that the examined remote sensing techniques can provide biomass estimates with smaller estimated errors than a field-based sample survey. The improvement can be highly significant, especially for LiDAR.
Forfattere
Odd-Jarle ØvreåsSammendrag
Det har vore stor nedgong i talet på storfe både på landsbasis (14 %) og på Vestlandet (17%) dei siste 10 åra. Produksjonen av storfekjøt er vidare intensivert med meir bruk av kraftfôr og mindre bruk av innhausta grovfôr og beite. Me har sett på kva endringar i biomasseuttak ein auke frå 0,5 % til 10 % kastratar vil medføre. Vidare har me jamført økonomien i kastratproduksjon og intensiv okseproduksjon.
Forfattere
Jan-Ole SkageSammendrag
Skog og landskap undersøker produksjonsevnen i mange forskjellige treslag, deriblant det fremmede nordamerikanske trelaget hemlokk. Hemlokk er blant annet plantet i et forsøksfelt i Stendadalen opp mot Stendafjellet på eiendommen til Stend videregående skole. Trærne der er nå over 80 år gamle, og det høyeste treet i feltet er blitt hele 38 meter, mens det grøvste treet er 57 centimeter i brysthøydediameter. Hemlokk er et treslag som produserer mye biomasse på Stend. Imidlertid forynger og sprer hemlokk seg lett i og rundt forsøksfeltet og er derfor planlagt hogget denne sommeren. Virket blir sannsynligvis levert til Tyskland.
Forfattere
Svein EilertsenSammendrag
Foreliggende konsekvensutredning knyttet til reindrift ved planlagt vindkraftverk i Fálesrášša,Kvalsund kommune, er en del av en helhetlig konsekvensutredning som er gjennomført på oppdrag fra tiltakshaver Finnmark Kraft AS. Gearretnarga reinbeitedistrikt (nr 21) bruker utredningsområdet som beiteland fra vår, gjennom sommeren og til høsten. Området er også kalvingsland for distriktet. Utredningsområdet har stor til middels stor verdi for reindrifta. Etablering av Fálesrášša vindkraftpark vil ha middels negative konsekvenser for reindrifta, i hovedsak som følge av forventet forstyrrelser på reinen og dermed endret arealbruk som resultat. Utbygger kan ta hensyn til reindrifta ved å unngå aktivitet i området når reinen er særlig sårbar for forstyrrelser (kalvingsperioden). Stengte tilførsels- og internveier for motorisert ferdsel og begrensing av friluftslivsaktiviteter i kalvingsperioden er foreslått somavbøtende tiltak for å redusere de negative konsekvensene for reindrifta.